1. Field of the Invention
The invention relates to a horizontal boring system with an improved boring bar and cutting blade. In more detail a system is devised for efficient boring of large diameter holes in alloys which were previously difficult or uneconomical to bore.
2. Prior Information Disclosure
Prior to preparing this application, a patentability search was performed and was conducted in class 408, subclasses 705, 200, 188 and 83 and the corresponding foreign classes. The search uncovered the following:
______________________________________ U.S. Pat. No. Inventor Date of Issue ______________________________________ 4,268,198 Peters, Robt. W. 5/19/81 4,265,574 Eckle, Otto 5/5/81 3,762,828 Faber, Kurt H. A. E. 10/2/73 3,759,625 Iversen, Normal H. 9/18/73 3,751,177 Faber, Kurt H. A. E. 8/7/73 3,389,621 Wear, Richard E. 6/25/68 ______________________________________
The search disclosure was of a machine tool for the metal working application of deep hole machining, including the geometry of the cutting insert holder.
In the patent to Eckle, U.S. Pat. No. 4,265,574 ('574), a combined boring and milling tool with at least three triangular shaped turnable cutter blades is provided. The relationship among the various cutting inserts is particularly shown and is described in detail therein. The particular milling depth is controlled and the effective cutting in relationship to the cutter blade is also described. Turning to Faber, a drill with guide device is shown in U.S. Pat. No. 3,762,828 ('828). In the guide device of this invention a ball holder with balls and elastic spacers are provided. The structure and the purpose of these guide balls are shown. It is specifically stated that such a structure is applicable to full face boring and core drilling. A similar guide provision is provided in Faber, U.S. Pat. No. 3,751,177 ('177) in which the guide pad is adapted to track the surface of the hole where the drill is operated. This guide pad differs from that shown in the prior Faber patent in that the guide pad is pivotally rockable on at least one axis. The arrangement of cutting hands as shown in Faber '177 and in Wear, U.S. Pat. No. 3,389,621 ('621) all seem to differ substantially from the arrangement of the cutting insert holding blade of the present disclosure. A similar analyses can be made of the Iversen U.S. Pat. No. 3,759,625 and the Peters U.S. Pat. No. 4,268,198.
With the aforementioned patents considered and evaluated, the structure of the present invention was viewed as being patentable thereover. No one of the patents when considered separately anticipated the invention at hand and no grouping thereof resulted in a reference rendering the invention obvious.
In the past, several technological problems have persisted with large diametered, deep hole machining. Among the commonest is the need for repetitive borings along the same axis to provide a hole with a larger and larger diameter until the desired diameter is achieved. In part, because of the repetitive nature of operations, tolerances, including deviation from centerline, circularity and surface finish, have all been quite difficult to maintain. Other problems addressed by this invention are cooling of cutting inserts, removal of chips, and the prolonging of cutting tool life.